The present invention relates to a coating composition improved in the resistance to fouling derived from water and oil repellency, the durability and the abrasion resistance, and in the release and exfoliation of stacked outer layer, and to a coated film and glass each having a coating layer comprised thereof.
Organosilane coating materials have technically been developed for use as maintenance-free coating materials which are advantageous for the resistance to weather (and sunlight), fouling, and so forth. The demand for improving the performance of organosilane coating materials is overwhelmingly increased. Therefore, it is now desired to provide coating materials which are improved in the coating appearance, the adhesiveness, the resistance to weather, heat, alkalis, organic chemicals, moisture, and (hot) water, the insulating property, the abrasion resistance, the resistance to fouling, and so forth.
Particularly for improving the resistance to fouling, it is known to make the surface of a coating hydrophilic. However, hydrophilization is a treatment to enhance the effect of washing and removing out of contaminants. Therefore, only in the case that the effect of washing overcomes the contamination, the hydrophilized coating shows the resistance to fouling. On the contrary, by the method of imparting the water and oil repellency to the coating layer, it is able to prevent the adhesiveness of both of hydrophilic and lipophilic contaminants. In prior art, addition of oils or surfactants to the coating composition is made in order to impart the water and oil repellency to the coating layer. By the addition of those, it is not able to maintain the abrasion resistance for a long period of time.
Further disclosed are a composition adapted for use as a composition which satisfies the requirements for performance of an organosilane coating material and composed mainly of a partial condensate of organosilane, a dispersion of colloidal silica, and an acrylic resin denatured by a silicone (See Japanese Patent Laid-open Publication (Sho) 60-135465), a composition composed mainly of a condensate of organosilane, a chelate compound of zirconium alkoxide, and a hydrolytic silyl-based vinyl resin (Japanese Patent Laid-open Publication (Sho) 64-1769), and a compound composed mainly of a condensate of organosilane, a colloidal alumina, and a hydrolytic silyl-based vinyl resin (See U.S. Pat. No. 4,904,721).
However, coatings made of the compositions disclosed in (Japanese Patent Laid-open Publication (Sho) 60-135465) and U.S. Pat. No. 4,904,721 have the disadvantage that their glittering property may be declined when they are exposed to ultraviolet light for a considerable length of time. Also, the composition disclosed in (Japanese Patent Laid-open Publication (Sho) 64-1769) is low in the storage stability; it may easily be turned to gel within a short period of time when its solid density is increased.
We, the inventors, have invented a composition for coating which includes a hydrolyzate and/or a partial condensate of organosilane, a vinyl resin having a silyl group wherein silicon atoms are bonded with a hydroxy group and/or a hydrolyzate, a metallic chelate compound, xcex2-diketone and/or xcex2-ketoester (See Japanese Patent Laid-open Publication (Hei) 5-345877). Since this composition has a favorable balance over the coating characteristics required for any organosilane coating material, new coating materials having more improvement in the coating characteristics such as the water and oil repellency and the smoothness of the surface of the coating layer shall be required.
Moreover, a coated film having photocatalytic function is proposed, formed by coating a film substrate. For example, in Japanese Patent Laid-open Publication (Hei) 9-227161, a self-cleaning film having a surface layer containing substantially transparent particles of a photocatalytic metal oxide on a film substrate surface, is disclosed. Also, a photocatalytic sheet having a photocatalytic coating formed on its upper surface and provided at its lower surface with an adhesive coating for attaching to another device or material to offer a photocatalytic function is disclosed in Japanese Patent Laid-open Publication (Hei) 9-313887. However, these coated films or sheets show the resistance to fouling by the highly hydrophilicity derived from photocatalyzation. Therefore, those show the effect only by irradiation and effect of removing out of contaminants only by washing or raining.
Moreover, an anti-fogging window glass having a surface layer provided on a window glass substrate and containing substantially transparent particles of a photocatalytic oxide is disclosed in Japanese Patent Laid-open Publication (Hei) 9-227161. The above glass may however show the effect only by irradiation and watering (raining), and easily fouled by oils because of its lipophilicity.
Also, a coated glass having a surface layer (10 to 200 nm thickness) composed of a photocatalytic metal oxide such as titanium dioxide provided on a glass substrate is disclosed in Japanese Patent Laid-open Publication (Hei) 9-235140. The coated glass is however regarded as inferior to the durability because it is provided without binder. Further, in Japanese Patent Laid-open Publication (Hei) 9-227159, an automobile window glass having a surface layer containing substantially transparent materials of a photocatalytic semiconductor on a glass substrate surface, is disclosed. The window glass is however regarded as inferior to the durability because of containing no binder.
The present invention has been invented in view of overcoming the foregoing technical drawbacks of the prior arts and its object is to provide a coating composition improved in the resistance to fouling derived from water and oil repellency, the durability and the abrasion resistance, and to a coated film and glass each having a coating layer comprised thereof.
1. A coating composition containing at least one component (a) selected from organosilanes, hydrolyzates of the organosilanes, and condensates of the organosilanes represented by Formula 1
(R1)nSi(OR2)4- nxe2x80x83xe2x80x83(1)
(wherein, R1 is a monovalent organic group having 1 to 8 carbon atoms: when two exist, they are either identical to or different from each other; R2 is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 6 carbon atoms: when two exist, they are either identical to or different from each other; and n is an integer ranging from 0 to 2);
and a polymer component (b) having a silyl group wherein silicon atoms are bonded with a hydrolytic group and/or a hydroxy group (referred to as a fluoropolymer having a silyl group hereinafter);
wherein the component (b) comprises a substance selected from polymers having a structural unit (b-1) expressed by Formula 2 (referred to as structural unit (b-1) hereinafter) 
xe2x80x83(wherein, R3 to R5 are CmY2m+1, m is an integer ranging from 0 to 5, and Y is selected from F, H, and Cl separately) and/or a structural unit (b-2) expressed by Formula 3 (referred to as structural unit (b-2) hereinafter) 
xe2x80x83(wherein, Rf is an alkyl group or an alkoxyalkyl group having fluorine atoms and R3 to R5 are analogous to those in Formula 2 or may be modified without departing from the term of analogy).
2. A coated film having a coating layer comprised of a coating composition according to item 1.
3. A coated film having a coating layer comprised of the composition (i) or (ii), wherein,
the composition (i) is a coating composition containing at least one component (a) selected from organosilanes, hydrolyzates of the organosilanes, and condensates of the organosilanes represented by Formula 1
(R1)nSi(OR2)4- nxe2x80x83xe2x80x83(1)
(wherein, R1 is a monovalent organic group having 1 to 8 carbon atoms: when two exist, they are either identical to or different from each other; R2 is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 6 carbon atoms: when two exist, they are either identical to or different from each other; and n is an integer ranging from 0 to 2), and
the composition (ii) is a coating composition containing the component (a) and a polymer component (bxe2x80x2) having a silyl group wherein silicon atoms are bonded with a hydrolytic group and/or a hydroxy group; and a coating layer comprised of a coating composition according to item 1 formed thereon.
4. A coated glass having a coating layer comprised of a coating composition according to item 1.
5. A coated glass having a coating layer comprised of the composition (i) or (ii), wherein,
the composition (i) is a coating composition containing at least one component (a) selected from organosilanes, hydrolyzates of the organosilanes, and condensates of the organosilanes represented by Formula 1
(R1)nSi(OR2)4- nxe2x80x83xe2x80x83(1)
(wherein, R1 is a monovalent organic group having 1 to 8 carbon atoms: when two exist, they are either identical to or different from each other; R2 is an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 6 carbon atoms: when two exist, they are either identical to or different from each other; and n is an integer ranging from 0 to 2), and
the composition (ii) is a coating composition containing the component (a) and a polymer component (bxe2x80x2) having a silyl group wherein silicon atoms are bonded with a hydrolytic group and/or a hydroxy group; and a coating layer comprised of a coating composition according to item 1 formed thereon.
The present invention will now be described in a sequence.
The composition (I) is a coating composition containing the following components (a).
Component (a)
The component (a) is at least a substance selected from organosilanes denoted by Formula 1 (referred to as organosilanes (1) hereinafter), hydrolyzates of the organosilanes (1), and condensates of the organosilanes (1) More specifically, the component (a) may be of one of the three groups or a mixture of any two groups or a mixture of all the three groups.
It should be noted that the hydrolyzate of an organosilane (1) is not limited to a particular one where all the OR2 groups, generally two to four, in the organosilane (1) have been hydrolyzated but may be prepared where one or two or more of the groups have been hydrolyzated or may be a mixture of those groups.
The condensate of an organosilane (1) has a Sixe2x80x94Oxe2x80x94Si bond where the silanol group in a hydrolyzate of the organosilane (1) has been condensed. It is not mandatory to condense all the silanol groups. The concept of a condensate of the organosilane (1) according to the present invention includes one where only a few of the silanol groups have been condensed and a mixture of condensates whose levels of condensation are different.
In Formula 1, characteristic examples of the monovalent organic group of R1 containing 1 to 8 carbon atoms are, for example, an alkyl group such as methyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, t-butyl, n-hexyl, n-heptyl, n-octyl, or 2-ethylhexyl; an acyl group such as acetyl, propionyl, butyryl, valeryl, benzoyl, trioyl, or caproyl; a vinyl group; an aryl group; a cyclohexyl group; a phenyl group; an epoxy group; a glycidyl group; a (meth)acryloxy group; an ureide group; an amide group; a fluoroacetoamide group; an isocyanate group and a fluoroalkyl group as well as their substituent derivatives.
The substituent group in the substituent derivative of R1 maybe selected of a set of halogen atoms, a substituted or not-substituted amino group, a hydroxy group, a mercapto group, an isocyanate group, a glycidoxy group, a 3,4-epoxycyclohexyl group, a (meth)acryloxy group, an ureide group, and an ammino-base. The number of carbon atoms in the substituent derivative of R1 including the carbon atoms in the substituent group is not greater than eight.
When two R1 groups exist in Formula 1, they may be either identical or different.
The alkyl group of R2 containing 1 to 5 carbon atoms may be, for example, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, t-butyl, and n-pentyl. The acyl group containing 1 to 6 carbon atoms may be, for example, acetyl, propionyl, butyryl, valeryl, and caproyl.
Two or more of the R2 groups in Formula 1 may be either identical or different from each other.
Characteristic examples of the organosilane (1) are tetra-alkoxysilanes including tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, and tetra-n-butoxysilane; trialkoxysilane including methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, 3-aminopropyl-trimethoxysilane, 3- aminopropyltriethoxysilane, 2-hydroxyethyl-trimethoxysilane, 2-hydroxyethyl-triethoxysilane, 2-hydroxypropyltrimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyl-trimethoxysilane, 3-hydroxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyl-triethoxysilane, 3-isocianatopropyltrimethoxysilane, 3-isocianatopropyltriethoxysilane, 3-glycidoxypropyl-trimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl) ethyltriethoxysilane, 3-(meth)-acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyl-triethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, nonafluorohexyl-trimethoxysilane, heptadecafluorodecyltrimethoxysilane, and tridecafluoroctyltrimethoxysilane; dialkoxysilanes including dimethyldirnethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-pentyldimethoxysilane, di-n-pentyldiethoxysilane, di-n-hexyldimethoxysilane, di-n-hexyldiethoxysilane, di-n-heptyldimethoxysilane, di-n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di-n-octyldiethoxysilane, di-n-cyclohexyldimethoxysilane, di-n-cyclohexyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, and heptadecafluorodecylmethyldimethoxysilane,; methyltriacetyloxysilane; and dimethyldiacetyloxysilan.
Preferably, it may be selected from trialkoxysilanes and dialkoxysilanes. As for trialkoxysilane, methyltrimethoxysilane, methyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, and 3-(meth)acryloxypropyltriethoxysilane are preferred. As for dialkoxysilane, dimethyldimethoxysilane and dimethyldiethoxysilane are preferred.
According to the present invention, the organosilane (1) may most preferably be trialkoxysilane or a combination of 40 to 95 mol % of trialkoxysilane and 60 to 5 mol % of dialkoxysilane. The use of dialkoxysilane with trialkoxysilane causes the resultant coating layer to be softened and increased in the resistance to alkalis.
The organosilane (1) may directly be used as a hydrolyzate and/or a condensate. The organosilane (1) employed as the hydrolyzate and/or the condensate enables to be utilized as the component (a) when it has been hydrolyzated and condensed. It is more preferable to perform the hydrolytic and condensing action of the organosilane (1) to yield the component (a) by feeding a proper amount of water during the preparation of the composition as a mixture of the organosilane (1) and the other components, as will explicitly be explained later. The amount of water based on the total amount of a structural unit denoted by (R1)nSiO(4- n)/2 according to the present invention is preferably from 0.5 to 3 moles and more preferably from 0.7 to 2 moles.
When a condensate is used as a component (a), weight-average molecular weight converted as Standard polystyrene (referred to as Mw hereinafter) of the used condensate preferably ranges from 800 to 100,000, more preferably from 1,000 to 50,000.
According to the present invention, the component (a) may be provided as a single substance or a mixture of two or more substances.
The component (a) may either partially or totally include a siloxane oligomer which has SiD bonds and of which the weight-average molecular weight ranges from 300 to 100,000.
The component (a) is commercially available as MKC silicate manufactured by Mitsubishi Chemical Corporation, an ethyl silicate manufactured by Colcoat Co., a silicon resin manufactured by Toray Industries, Inc./Dow-Corning Co., a silicon resin manufactured by Toshiba Silicones Co., a silicon resin manufactured by Shin-Etsu Chemical Co., Ltd., a hydroxyl contained polydimethylsiloxane manufactured by Dow-Corning Asia Co., and a silicon oligomer manufactured by Nippon Unicar Company Limited. In the present invention, those products may be used directly or after subjected to the condensation.
In the present invention, the component (a) may be provided as a single substance or a mixture of two or more substances.
Component (b) (Fluoropolymer Having a silyl Group)
In the invention, component (b) is a fluoropolymer having a structural unit (b-1) and a structural unit (b-2), in which a silyl group having silicon atoms bonded with a hydrolytic group and/or a hydroxy group (referred to as a specific silyl group hereinafter), preferably, is linked to the end and/or side of a molecular chain of the polymer.
The amount of silicon atoms in the component (b) is generally 0.1 to 60 mol % and preferably 0.5 to 50 mol %, based on the total amount of the component (b2).
A preferable form of the specific silyl group is expressed by Formula 4: 
(wherein, X is a hydrolytic group or hydroxy groups of halogen atoms, an alkoxy group, an acetoxy group, a phenoxy group, a thioalkoxy group, or an amino group, R6 is hydrogen atoms, an alkyl group having 1 to 10 carbon atoms, or an aralkyl group having 1 to 10 carbon atoms, and i is an integer ranging from 1 to 3).
The component (b) is preferably obtained by polymerizing a monomer (referred to as a monomer (b-1) hereinafter) having the structure unit denoted by Formula 2 and/or a monomer (referred to as a monomer (b-2) hereinafter) having the structural unit denoted by Formula 3 and a monomer (referred to as a monomer (b-3) hereinafter) wherein a set of silicon atoms are bonded to the hydrolytic group and/or the hydroxy group in the specific silyl group and may further be added with another monomer (referred to as a monomer (b-4) hereinafter) which can copolymerize with the foregoing monomers. The monomer (b-4) may contain fluorine atoms which are absent in the other monomers (b-1) and (b-2)
The component (b) may also be a polymer obtained by polymerizing the monomer (b-1) and/or the monomer (b-2); the polymer may be added with the monomer (b-4), if desired, the polymer is modified by reaction with a silane compound (referred to as a silane compound (b-5) hereinafter) which has a functional group capable of reacting with the hydrolytic group or the hydroxy group.
Monomer (b-1)
The monomer (b-1) is expressed by Formula 2xe2x80x2, 
(wherein, R3 to R5 are CmY2m+1, m is an integer ranging 0 to 5, and Y is selected from F, H, and Cl separately).
The monomer (b-1) may be a compound having a polymerizable unsaturated double bond and at least one fluorine atom.
More particularly, the monomer (b-1) may be selected from:
(A) fluoroethylenes including CF2xe2x95x90CF2, CHFxe2x95x90CF2, CH2xe2x95x90CF2, CH2xe2x95x90CHF, CClFxe2x95x90CF2, CHClxe2x95x90CF2, CCl2xe2x95x90CF2, CClFxe2x95x90CClF, CHFxe2x95x90CCl2, CH2xe2x95x90CClF, and CCl2xe2x95x90CClF;
(B) fluoropropenes including CF3CFxe2x95x90CF2, CF3CFxe2x95x90CHF, CF3CHxe2x95x90CF2, CF3CFxe2x95x90CH2, CF3CFxe2x95x90CHF, CHF2CFxe2x95x90CHF, CF3CHxe2x95x90CH2, CH3CFxe2x95x90CF2, CH3CHxe2x95x90CF2, CF3CFxe2x95x90CH2, CF2ClCFxe2x95x90CF2, CF3CClxe2x95x90CF2, CF3CFxe2x95x90CFCl, CF2ClCClxe2x95x90CF2, CF2ClCFxe2x95x90CFCl, CF2CCl=CClF, CF2CClxe2x95x90CCl2, CCl3CFxe2x95x90CF2, CF2ClCClxe2x95x90CCl2, CFCl2CClxe2x95x90CCl2, CF3CFxe2x95x90CHCl, CClF2CFxe2x95x90CHCl, CF3CClxe2x95x90CHCl, CHF2CClxe2x95x90CCl2, CF2ClCHxe2x95x90CCl2, CF2ClCClxe2x95x90CHCl, and CCl3CFxe2x95x90CHCl; and
(C) Fluoroolefines having not smaller than four carbon atoms including CF3CF2CFxe2x95x90CF2, CF3CFxe2x95x90CFCF3, CF3CHxe2x95x90CFCF3, CF2xe2x95x90CFCF2CHF2, CF3CF2CFxe2x95x90CH2, CF2CHxe2x95x90CHCF3, CF2xe2x95x90CFCF2CH3, CF2xe2x95x90CFCH2CH3, CF3CH2CHxe2x95x90CH2, CF3CHxe2x95x90CHCH3, CF2xe2x95x90CHCH2CH3, CH3CF2CHxe2x95x90CH2, CFH2CHxe2x95x90CHCFH2, CH3CF2CHxe2x95x90CH2, CH2xe2x95x90CFCH2CH3, CF3(CF2)2CFxe2x95x90CF2, and CF3(CF2)2CFxe2x95x90CF2.
The monomer (b-1) having fluorine atoms may be provided in the form of a single monomer or a combination of two or more monomers.
Monomer (b-2)
The monomer (b-2) is expressed by Formula 3xe2x80x2, 
(wherein, Rf is an alkyl group or an alkoxyalkyl group having fluorine atoms and R3 to R5 are analogous to those of Formula 2xe2x80x2 but may be modified without departing from the term of analogy to Formula 2xe2x80x2).
The monomer (b-2) may be a compound having a polymerizable unsaturated double bond, an ether bond, and at least one fluorine atom.
More particularly, the monomer (b-2) may be selected from:
(A) (fluoroalkyl) vinyl ether or (fluoroalkoxyalkyl) vinyl ether expressed by CH2xe2x95x90CHxe2x80x94Oxe2x80x94Rf (wherein, Rf is an alkyl group or an alkoxyalkyl group having fluorine atoms);
(B) perfluoroalkyl vinyl ethers including perfluoromethyl vinyl ether, perfuoroethyl vinyl ether, perfluoroprolyl vinyl ether, perfluorobutyl vinyl ether, and perfluoroisobutyl vinyl ether; and
(C) perfluoroalkoxyalkyl vinyl ethers including perfluoropropoxypropyl vinyl ether.
The monomer (b-2) having fluorine atoms may be provided in the form of a single monomer or a combination of two or more monomers.
When the two monomers (b-1) and (b-2) are used in a combination, they may preferably be hexafluoropropylene and perfluoroalkyl perfluorovinyl ether or perfluoroalkoxyalkyl perfluorovinyl ether.
Monomer (b-3)
The monomer (b-3) is a monomer having a polymerizable unsaturated double bond in one molecule and silicon atoms bonded to a hydrolytic group and/or a hydroxy group.
The monomer (b-3) maybe an unsaturated silane compound expressed by Formula 4xe2x80x2 (referred to as an unsaturated silane compound). 
(wherein, X, R6 and i are analogous to those of Formula 4xe2x80x2 and R7 is an organic group having a polymerizable unsaturated double bond).
Characteristic examples of the unsaturated silane compound are:
CH2xe2x95x90CHSi(CH3)(OCH3)2, CH2xe2x95x90CHSi(OCH3)3, CH2xe2x95x90CHSi(OC2H5)3, CH2xe2x95x90CHSi(CH3)Cl2, CH2xe2x95x90CHSiCl3, CH2xe2x95x90CHCOO(CH2)2Si(CH3)(OCH3)2, CH2xe2x95x90CHCOO(CH2)2Si(OCH3)3, CH2xe2x95x90CHCOO(CH2)3Si(CH3)(OCH3)2, CH2xe2x95x90CHCOO(CH2)3Si(OCH3)3, CH2xe2x95x90CHCOO(CH2)2Si(CH3)Cl2, CH2xe2x95x90CHCOO(CH2)2SiCl3, CH2xe2x95x90CHCOO(CH2)3Si(CH3)Cl2, CH2xe2x95x90CHCOO(CH2)3SiCl3, CH2xe2x95x90C(CH3)COO(CH2)2Si(CH3)(OCH3)2, CH2xe2x95x90C(CH3)COO(CH2)2Si(OCH3)3, CH2xe2x95x90C(CH3)COO(CH2)3Si(CH3)(OCH3)2, CH2xe2x95x90C(CH3)COO(CH2)3Si(OCH3)3, CH2xe2x95x90C(CH3)COO(CH2)2Si(CH3)Cl2, CH2xe2x95x90C(CH3)COO(CH2)2SiCl3, CH2xe2x95x90C(CH3)COO(CH2)3Si(CH3)Cl2, and CH2xe2x95x90C(CH3)COO(CH2)3SiCl3, 
The compound may be provided in the form of a single compound or a combination of two or more compounds. Monomer (b-4)
The monomer (b-4) capable of copolymerizing with the monomers (b-1) to (b-3) may be selected from:
(A) alkyl (meth)acrylates including methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, amyl (meth)acrylate, i-amyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, and cyclohexyl (meth)acrylate;
(B) aromatic vinyl monomers including styrene, xcex1-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methoxystyrene, 2-hydroxymethylstyrene, 4-ethylstyrene, 4-ethoxystyrene, 3,4-dimethylstyrene, 3,4-diethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chloro-3-methylstyrene, 4-t-butylstyrene, 2,4-dichlorostyrene, 2,6-dichlorostyrene, and 1-vinylnaphthalene;
(C) hydroxyalkyl(meth)acrylates including hydroxymethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxyamyl(meth)acrylate, hydroxyhexyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, and n-octyl(meth)acrylate;
(D) epoxy containing monomers including glycidyl(meth)acrylate, and methylglycidyl(meth)acrylate;
(E) multi-functional monomers including divinylbenzene, ethyleneglycol-di(meth)acrylate, diethyleneglycol-di(meth)acrylate, triethyleneglycoldi(meth)acrylate, tetraethyleneglycol-di(meth)acrylate, propyleneglycol-di(meth)acrylate, dipropyleneglycoldi(meth)acrylate, tripropyleneglycol-di(meth)acrylate, tetrapropyleneglycol-di(meth)acrylate, butanedioldi(meth)acrylate, hexanediol-di(meth)acrylate, trimethylolpropane-tri(meth)acrylate, and pentaerythritol-tetra(meth)acrylate;
(F) acid amide compounds including (meth)acrylamide, N-methylol(meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide, N,Nxe2x80x2-methylenebisacrylamide, diacetoneacryleamide, maloamide, and maleimide;
(G) vinyl compounds including vinyl chloride, vinylidene chloride, and vinylesters of fatty acids;
(H) aliphatic conjugated dienes including 1,3-butadiene, 2-methyl-1,3-butadinene, 2,3-dimethyl-1,3-butadiene, 2-neopentyl-1,3-butadinene, 2-chloro-1,3-butadinene, 2-cyano-1,3-butadinene, isoprene, conjugated pentadiene having straight-chain substituted with a substituent group such as an alkyl group, halogen atoms, or a cyano group, and conjugated hexadinene having straight-chain or side-chain;
(I) ethylene type unsaturated carboxylic acids including (meth) acrylic acid, fuumaric acid, itaconic acid, monoalkyl itaconic acids, maleic acid, crotonic acid, and 2-(meth)acryloyloxyethylhexahydrophthalic acid;
(J) vinyl cyanide compounds including acrylonitrile and methacrylonitrile;
(K) piperidine monomers including 4-(meth)acryloyloxy-2,2,6,6,-tetramethylpiperidine, 4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, and 4-(meth)acryloyloxy-1,2,2,6,6-pentamethylpiperidine;
(L) vinyl ether monomers including vinyl glycidyl ether, 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 2-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 3-hydroxybutyl vinyl ether, 5-hydroxypentyl vinyl ether, and 6-hydroxyhexyl vinyl ether;
(M) allylethers including allyl glycidyl ether, 2-hydroxyethyl allyl ether, 4-hydroxybutyl allyl ether, and glycerol monoallyl ether
(N) alkyl vinyl ethers and cycloalkyl vinyl ethers including methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, iso-propyl vinyl ether, n-butyl vinyl ether, iso-butyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, n-dodecyl vinyl ether, 2-ethylhexyl vinyl ether, and cyclohexyl vinyl ether;
(O) fluoro(meth)acrylates including 2,2,2-trifluoroethyl (meth)acrylate, 2,2,3,3,3-pentafluoropropyl(meth)acrylate, 2-(perfluorobuthyl)ethyl (meth)acrylate, 2-(perfluorohexyl)ethyl (meth)acrylate, 2-(perfluorooctyl)ethyl (meth)acrylate, 2-(perfluorodecyl)ethyl (meth)acrylate, 2H,1H,5H-octafluoropentyl(meth)acrylate, and 1H,1H,2H,2H-heptadecafluorodecyl(meth)acrylate;
and other substances including dicaprolactone.
This type of the monomers may be provided in the form of a single monomer or a combination of two or more monomers.
Monomer (b-5) (silane compound)
The silane compound (b-5) used in the addition reaction, for example, halogenated silanes including methyldichlorosilane, trichlorosilane, and phenyldichlorosilane; alkoxysilanes including methyldimethoxysilane, methyldiethoxysilane, phenyldimethoxysilane, trimethoxysilane, and triethoxysilane; acyloxysilanes including methyldiacetoxysilane, phenyldiacetoxysilane, and triacetoxysilane.
These silane compounds may be provided as a single compound or a combination of two or more compounds.
The polymerization of producing the component (b) may be implemented by a process of feeding the monomers at once for polymerization, a process of polymerizing some of the monomers and then continuously or intermittently feeding the remaining monomers, or a process of feeding the monomers in succession throughout polymerization. Also, any combination of the polymerizing processes may be employed. Most preferable is a technique of solution polymerization. The solvent used in the solution polymerization is any commonly available solvent and may preferably be selected from ketones, alcohols, and esters. For the polymerization, a polymerizing initiator, a molecular weight modifier, a chelating agent, and an inorganic electrolyte may be selected from common agents.
The amount of a sum of the structural units (b-1) and (b-2) in the component (b) is generally 0.5 to 80 mol % and preferably 1 to 70 mol %, based on the total amount of the component (b). When the amount is lower than 0.5 mol %, the resultant coating layer may hardly be improved in the transparency and the adhesiveness while repelling water and oils. If higher than 80 mol %, the adhesiveness of the coating layer to a substrate may be declined.
The amount of the structural unit (b-1) is preferably 0.5 to 70 mol %, based on the total amount of the component (b). The amount of the structural unit (b-2) is preferably 0.5 to 70 mol %, based on the total amount of the component (b).
With respect to the amount of the structural unit (b-3), the amount of the specific silyl group is generally 0.1 to 60 mol % and preferably 0.5 to 50 mol %, based on the total amount of the component (b). When the amount is lower than 0.1 mol %, the effect of condensation together with the component (a) will hardly be ensured. If higher than 60 mol %, the storage stability of the resultant coating composition will be declined.
The amount of the structural unit (b-4) composed of the monomer (b2-4) capable of copolymerizing with the other monomers is generally not higher than 90 mol % and preferably not higher than 80 mol %, based on the total amount of the component (b).
Mw of the component (b) is preferably 1,000 to 50,000 and more preferably 5,000 to 30,000.
In the invention, the component (b) may be provided in the form of a single substance or a combination of two or more substance as described above.
The amount of the component (b) in the coating composition is generally 20 to 500 weight parts, preferably 25 to 400 weight parts, and more preferably 50 to 300 weight parts, based on 100 weight parts of the structural unit (R1)nSiO(4-n)/2 in the component (a). When the amount of component (b) is smaller than 20 weight parts, the resultant coating layer will be declined in the resistance to alkalis and cracking. If greater than 500 weight parts, the resistance to weather of the coating layer will be declined.
In the present invention, a vinyl copolymer having the specific silyl group and having no fluorine atoms (referred to as component (bxe2x80x2) hereinafter) may be used in addition to the component (b) without impairing the effect of the invention. The component (bxe2x80x2) is provided by copolymerization of the foregoing monomers (b-3) and (b-4) or addition reaction of a polymer obtained from the monomer (b-4) with a silane compound (b-5). In the coating composition of the invention, the amount of the component (bxe2x80x2) is generally not greater than 500 weight parts, based on 100 weight parts of the structural unit (R1)nSiO(4-n)/2 of the component (a).
According to the present invention, an organic solvent is used to obtain a uniform mixture of the component (a), the component (c), and the other relevant components (c) to (e), and to have a desired concentration of all solids in the composition. In addition, the organic solvent may assist each of a variety of coating processes and thus increase the dispersion stability and the storage stability of a resultant coating composition.
The organic solvent used for mixing up the components uniformly is of no limitations and may be selected from, for example, alcohols, aromatic hydrocarbons, ethers, ketones, and esters.
The alcohols for the organic solvent include specifically methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, n-hexyl alcohol, n-octyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene monomethyl ether acetate, and diacetone alcohol.
The aromatic hydrocarbons include specifically benzene, toluene, and xylene. The ethers include specifically tetrahydrofuran and 1,4-dioxane. The ketones include specifically acetone, methyl ethyl ketone, methyl isobutyl ketone, and di-isobutyl ketone. The esters include specifically ethyl acetate, propyl acetate, butyl acetate, and propylene carbonate.
The organic solvent may be provided as a single solvent or a combination of two or more solvents.
While coating composition of the invention is able to provide a coating layer improved in the resistance to fouling derived from water and oil repellency, it is favorable to form a undercoating layer on the substrate surface in order to impart the functions of the long-term adhesiveness and shield from ultraviolet ray. Preferable examples of the undercoating composition for a undercoating layer are the compositions (i) and (ii). The composition (i) is more preferable.
The undercoating compositions (i) and (ii) will be explained in detail below.
The undercoating composition (i) contains the above component (a). For preparing the composition (i), water is added to carry out the hydrolysis and condensation of the organosilane (1) preferably. Further, hydrolyzates and/or condensates of the organosilane (1) can be used as component (a).
The undercoating composition (ii) contains the above component (a) and silyl group having polymer (bxe2x80x2). Componet (bxe2x80x2) (silyl group having polymer)
The component (bxe2x80x2) is a polymer in which no fluorine is contained and a silyl group is linked to the end and/or side of a molecular chain of the polymer. The component (bxe2x80x2) in the composition (ii) allows the hydrolytic and/or hydroxy groups in its specific silyl group to be condensed together with the component (a) thus contributing to the improvement in the coating layer characteristics.
The amount of silicon in the component (bxe2x80x2) is generally 0.001 to 20 percent by weight and preferably 0.01 to 15 percent by weight, based on the total amount of the component (bxe2x80x2).
A preferable form of the specific silyl group is expressed by above Formula 4.
The component (bxe2x80x2) (silyl group having polymer) is provided by the method of producing the component (b) (fluoropolymer having a silyl group) while using at least one kind of monomers lacking in fluorine selected from the monomers showed as monomer (b-4) in place of monomers (b-1) and (b-2).
Alternatively, the component (bxe2x80x2) may be selected from epoxy resins containing the specific silyl group and polyester resins containing the specific silyl group.
The epoxy resin containing the specific silyl group may be produced by causing the epoxy group in an epoxy resin such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, aliphatic poly(glycidyl ether), or aliphatic poly(glycidyl ester) to react with aminosilanes, vinylsilanes, carboxysilanes, or glycidylsilanes having the specific silyl group.
The polyester resin containing the specific silyl group may be produced by causing the carboxyl group or hydroxy group in a polyester resin to react with aminosilanes, carboxysilanes, or glycidylsilanes having the specific silyl group.
Mw of the component (bxe2x80x2) ranges preferably 2,000 to 100,000 and more preferably 4,000 to 50,000.
The amount of the component (bxe2x80x2) used in the composition (ii) is generally 2 to 900 weight parts, preferably 10 to 850 weight parts, and more preferably 20 to 800 weight parts, based on 100 weight parts of the structural unit (R1)nSiO(4-n)/2 in the component (a). In that case, when the amount of component (bxe2x80x2) is smaller than 2 weight parts, its resultant coating layer will be declined in the resistance to alkalis. If higher than 900 weight parts, the resistance to weather of the coating layer throughout a long period of time will be lowered.
According to the invention, the component (bxe2x80x2) may be provided in the form of a single substance or a combination of two or more substance as described above.
Preferably, the component (b) in the composition (ii) may be condensed together with the component (a) under the presence of water and/or an organic solvent.
The kind and the amount of component (a) in composition (ii) is the same as the above coating composition.
Each of the coating composition of the invention and compositions (i) and (ii) may further be added with the following components (c) to (e) as well as other additives, which will be explained below.
The component (c) is a catalyst for encouraging the hydrolysis and condensation of the components (a), (b) and (bxe2x80x2).
The use of the component (c) will accelerate the speed of curing the resultant coating layer and increase the molecular weight of polysiloxane produced by poly condensation of the organosilane component, hence allowing the resultant coating layer to be improved in the physical strength and the long-term durability as well as making the coating layer thickness increased and facilitating the coating application.
The component (c) is preferably selected from acidic compounds, basic compounds, metallic salts, amine compounds, and organometallic compounds and/or their partial hydrolyzates (the organometallic compounds and/or their partial hydrolyzates being referred to as organometallic compounds).
Characteristic examples of the acidic compound are acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, alkyltitanic acid, p-toluenesulphonic acid, and phthalic acid and it may preferably be acetic acid.
Characteristic examples of the basic compound are sodium hydroxide and potassium hydroxide and it may preferably be sodium hydroxide.
Characteristic examples of the metallic salts are alkali metallic salts of naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminic acid and carbonic acid.
Characteristic examples of the amine compound are ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, piperidine, piperadine, m-phenylenediamine, p-phenylenediamine, ethanolamine, triethylamine, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)-aminopropyltrimethoxysilane, 3-(2-aminoethyl)-aminopropyltriethoxysilane, 3-(2-aminoethyl)-aminopropylmethyldimethoxysilane, 3-anilinopropyltrimethoxysilane, alkylamine salts, quaternary ammonium salts, and modified amines used as a hardener for epoxy resin, and preferably it may be 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, or 3-(2-aminoethyl)-aminopropyltrimethoxysilane.
The organometallic compound may be selected from a particular compound expressed by Formula 5 shown below (referred to as anorganometallic compound (5) hereinafter), an organometallic compound of tetravalent tin having 1 to 2 alkyl groups where 1 to 10 carbon atoms are bonded to the corresponding number of tin atoms (referred to as an organic tin compound hereinafter), and their hydrolyzates.
M(OR8)p(R9COCHCOR10)qxe2x80x83xe2x80x83(5)
(wherein, M is zirconium, titanium, or aluminum, R8 and R9, different or identical to each other, are monovalent hydrocarbon groups having 1 to 6 carbon atoms such as ethyl, n-propyl, i-propyl, n-butyl, i-butyl, sec-butyl, t-butyl, n-pentyl, n-hexyl, cyclohexyl, or phenyl, R10 is a monovalent hydrocarbon group having 1 to 6 carbon atoms, like R8 or R9, or an alkoxyl group having 1 to 16 carbon atoms such as methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, sec-butoxy, t-butoxy, lauryloxy, or stearyloxy, and p and q are integers ranging from 0 to 4, (p+q)=(valence of M).)
The organometallic compound (5) may be selected from:
(A) organic zirconium compounds including zirconium tetra-n-butoxide, zirconium tri-n-butoxyethylacetoacetate, zirconium di-n-butoxy-bis(ethylacetoacetate), zirconium n-butoxy-tris(ethylacetoacetate), zirconium tetrakis(n-propylacetoacetate), zirconium tetrakis(acetylacetoacetate), and zirconium tetrakis(ethylacetoacetate);
(B) organic titanium compounds including titanium tetra-i-propoxide, titanium di-i-propoxy bis(ethylacetoacetate), titanium di-i-propoxy bis (acetylacetate), and titanium di-i-propoxy bis(acetylacetone); and
(C) organic aluminum compounds including aluminum tri-i-propoxide, aluminum di-i-propoxy ethylacetoacetate, aluminum di-i-propoxy acetylacetonate, aluminum i-propoxy bis(ethylacetoacetate), aluminum 1-propoxy bis(acetylacetonate), aluminum tris(ethylacetoacetate), aluminum tris(acetylacetonate), and aluminum monoacetylacetonate-bis(ethylacetoacetate).
The organometallic compound (5) and its partial hydrolyzate may preferably be selected from zirconium tri-n-butoxy-ethylacetoacetate, titanium di-i-propoxy bis(acetylacetonate), aluminum di-i-propoxy ethylacetoacetate, aluminum tris (ethylacetoacetate), and their partial hydolyzates.
The organic tin compound may be selected from:
carbonic acid organic tin compounds including (C4H9)2Sn(OCOC11H23)2, (C4H9)2Sn(OCOCHxe2x95x90CHCOOCH3)2, (C4H9)2Sn(OCOCHxe2x95x90CHCOOC4H9)2, (C8H17)2Sn(OCOC8H17)2, (C8H17)2Sn(OCOC11H23)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOCH3)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOC4H9)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOC8H17)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOC16H33)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOC17H35)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOC18H37)2, (C8H17)2Sn(OCOCHxe2x95x90CHCOOC20H41)2, 
(C4H9)Sn(OCOC11H23)3, and (C4H9)Sn(OCONa)3;
mercaptide organic tin compounds including
(C4H9)2Sn(SCH2COOC8H17)2, (C4H9)2Sn(SCH2CH2COOC8H17)2, (C8H17)2Sn(SCH2COOC8H17)2, (C8H17)2Sn(SCH2CH2COOC8H17)2, (C8H17)2Sn(SCH2COOC12H25)2, (C8H17)2Sn(SCH2CH2COOC12H25)2, (C4H9)Sn(SCOCHxe2x95x90CHCOOC8H17)3, (C8H17)Sn(SCOCHxe2x95x90CHCOOC8H17)3, 
sulfide organic tin compounds including (C4H9)Snxe2x95x90S, (C8H17)2Snxe2x95x90S, and 
chloride organic compounds including (C4H9)SnCl3,
(C4H9)2SnCl2, (C8H17)2SnCl2, and 
organic tin oxides including (C4H9)2SnO and (C8H17)2SnO as well as reaction products produced by the reaction between these organic tin oxide and an ester compound such as ethyl silicate, dimethyl maleate, diethyl maleate, or dioctyl phthalate.
The component (c) maybe provided in the form of a single substance or a combination of two or more substances and may be mixed with a zinc compound or a reaction retardant.
The component (c) may also be fed at a stage for preparation of the composition or at a stage where a coating layer is formed or at both the stages for preparation of the composition and for forming the coating layer.
The amount of the component (c), except the organometallic compounds, based on 100 weight parts of the structural unit, (R1)nSiO(4-n)/2, in the component (a) is generally 0 to 100 weight parts, preferably 0.01 to 80 weight parts, and more preferably 0.1 to 50 weight parts. The amount of the component (c) of any organometallic compound based on 100 weight parts of the structural unit, (R1)nSiO(4-n)/2, in the component (a) is generally 0 to 100 weight parts, preferably 0.1 to 80 weight parts, and more preferably 0.5 to 50 weight parts. When the amount of the component (c) exceeds 100 weight parts, the composition will be declined in the storage stability and its resultant coating layer will suffer from cracking.
The component (d) may be at least one expressed by Formula 6 and selected from xcex2-diketones, xcex2-ketoesters, carbonic acid compounds, compounds having two hydroxy groups, amine compounds, and oxyaldehydes.
R9COCH2COR10xe2x80x83xe2x80x83(6)
(wherein, R9 and R10 are analogous to those in Formula 5).
The component (d) is preferably added when an organometallic compound is used as component (c).
The component (d) serves as a stability enhancing agent for the composition. More specifically, it is presumed that the component (d) is coordinates bonded to metallic atoms in the organometallic compound thus to appropriately control the promotion of co-condensation of the components (a), (b), and (bxe2x80x2) with the organometallic compound, hence improving the storage stability of the composition.
Characteristic examples of the component (d) are acetylacetone, methyl acetoacetate, ethyl acetoacetate, n-propyl acetoacetate, i-propyl acetoacetate, n-butyl acetoacetate, sec-butyl acetoacetate, t-butyl acetoacetate, hexane-2,4-dione, heptane-3,5-dione, octane-2,4-dione, nonane-2,4-dione, 5-methylhexane-2,4-dione, malonic acid, oxalic acid, phthalic acid, glycolic acid, salicylic acid, amino acetic acid, imino acetic acid, ethylenediaminetetraacetic acid, glycol, catechol, ethylenediamine, 2,2-bipyridine, 1,10-phenanthroline, diethylenetriamine, 2-ethanolamine, dimethylglyoxime, dithizone, methionine, and salicylaldehyde. It may preferably be acetylacetone or ethyl acetoacetate.
The component (d) maybe provided in the form of a single substance or a combination of two or more substances.
The amount of the component (d) based on 1 mole of the organometallic compound is generally not smaller than 2 moles and preferably 3 to 20 moles. When the amount of the component (d) is smaller than 2 moles, improvement in the storage stability of the resultant composition will be uncertain.
The component (e) is a powder and/or a sol or a colloid form of an inorganic compound having no photocatalytic function and may be fed so that the resultant coating layer has desired properties.
Characteristic examples of the component (e) are SiO2, Al2O3, AlGaAs, Al (OH)3, Sb2O5, Si3N4, SnO2, Snxe2x80x94In2O3, In2O3, Sbxe2x80x94In2O3, InSb, InAs, InGaAlP, MgF, CeF3, CeO2, 3Al2O3xe2x80x942SiO2, BeO, SiC, AlN, Fe, Fe2O3, Co, Coxe2x80x94FeOx, CrO2, Fe4N, BaTiO3, BaOxe2x80x94Al2O3xe2x80x94SiO2, Ba ferrite, SmCO5, YCO5, CeCO5, PrCO5, Sm2CO17, Nd2Fe14B, ZnO2, Al4O3, AlN, SiC, xcex1-Si, SiN4, CoO, Sb2O5, MnO2, MnB, Co3O4, Co3B, LiTaO3, MgO, MgAl2O4, BeAl2O4, ZrSiO4, ZnO, ZnS, ZnSe, ZnSb, ZnTe, PbTe, PbS, PbSe, GeSi, FeSi2, CrSi2, CoSi2, MnSi1.73, Mg2Si, xcex2-B, BaC, BP, TiB2, ZrB2, HfB2, Ru2Si3, RuO2, TiO2, TiO3, SrTiO3, FeTiO3, PbTiO3, Al2TiO5, Zn2SiO4, Zr2SiO4, 2MgO2xe2x80x94Al2O3xe2x80x945SiO2, WO3, Bi2O3, CdO, CdS, CdSe, GaP, GaAs, CdFeO3, MoS2, LaRhO3, GaN, CdP.,Nb2O5, GaAsP, Li2Oxe2x80x94Al2O3xe2x80x944SiO2, Mg ferrite, Ni ferrite, Nixe2x80x94Zn ferrite, Li ferrite, and Sr ferrite.
The component (e) may be provided in the form of a single substance or a combination of two or more substances.
The colloidal silica form of the component (e) may commercially be available as, for example, Snowtex, Isopropanol Silicasol, and Methanol Silicasol by Nissan Chemical Industries, Ltd; Cataloid and Oscar by Catalysts and Chemicals Industries Co., LTD; Ludox by Du pont, U.S.A.; Syton by Monsanto, U.S.A., and Nalcoag by Nalco Chemical, U.S.A. The colloidal alumina form of the component (e) may be available asAlminasol-100, and Aluminasol-520 by Nissan Chemical Industries, Ltd.
In order to impart photocatalytic function, the component (e) may include TiO2 (preferably Anatase type). The component (e) may also include CeO2 or ZnO which acts as an ultraviolet ray absorber.
The average particle diameter of the component (e) is preferably 30 xcexcm or less, more preferably 0.005 to 20 xcexcm, most preferably 0.005 to 10 xcexcm. If the average particle diameter is more than 30 xcexcm, the smoothness of the surface of the coating is not achieved.
The component (e) may also be provided in a powder form, an aqueous sol or colloidal form where the substance is dispersed in water, or a solvent sol or colloidal form where the substance is dispersed in a polar solvent such as isopropyl alcohol or a less-polar solvent such as toluene. The component (e) of the solvent sol or colloidal form may further be diluted with water or the solvent depending on the dispersing properties of the component (e) or may be surface-treated for improving the dispersing properties.
When the component (e) is the aqueous sol or colloidal form, its solid concentration may preferably be not greater than 40 percent by weight.
The method of combining the component (e) with the composition may involve feeding the component (e) after the preparation of the composition or feeding the same during the preparation of the composition to allows the hydrolysis and co-condensation with the components (a), (b), and (bxe2x80x2) or their condensates.
The amount of the component (e) based on 100 weight parts of the structural unit, (R1)nSiO(4xe2x88x92n)/2, in the component (a) is generally 0 to 500 weight parts and preferably 0.1 to 400 weight parts in solid state.
The coating composition of the present invention may be added with the optional components described later.
The coating composition may include an organic ultraviolet ray absorber and a stabilizer. Specific examples of the organic ultraviolet ray absorber are benzophenones, benzotriasols, triadines, and phenols. And specific examples of the stabilizer are hindered amines. These additives may be provided in the form of a single substance or structural unit of a copolymer.
The composition of the present invention may have an appropriate filler added and dispersed for improving the color and the thickness of a resultant coating layer.
The filler may be selected from non-aqueous organic pigments, non-aqueous inorganic pigments, ceramics, metals, and alloys of a particle, fiber, or scale form, and their oxides, hydroxides, carbides, nitrides, and sulfides.
Characteristic examples of the filler are iron, copper, aluminum, nickel, silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium dioxide for pigment, aluminum oxide, chrome oxide, manganese oxide, iron oxide, zirconium oxide, cobalt oxide, synthetic mullite, aluminum hydroxide, iron hydroxide, silicon carbide, silicon nitride, boron nitride, clay, diatom earth, slaked lime, gypsum, talc, barium carbonate, calcium carbonate, magnesium carbonate, barium sulfate, bentonite, mica, zinc green, chrome green, cobalt green, viridian, Guignet""s green, cobalt chrome green, shale green, green soil, manganese green, pigment green, ultramarine, deep blue, pigment blue, rockyblue, cobalt blue, cerulean blue, copper borate, molybdenum blue, copper sulfide, cobalt purple, mars violet, manganese purple, pigment violet, lead suboxide, calciumhydrochloride, zinc yellow, lead sulfide, chrome yellow, yellow soil, cadmium yellow, strontium yellow, titanium yellow, litharge, pigment yellow, copper suboxide, cadmium red, selenium red, chrome vermilion, Indian red, zinc white, antimony white, basic lead sulfate, titanium white, lithopone, lead silicate, zirconium oxide, tungsten white, lead, zinc white, Bantison white, lead phthalate, manganese white, lead sulfate, carbon black, bone black, diamond black, Thermatomic black, plant black, potassium titanate whisker, and molybdenum disulfide.
The filler may be provided in the form of a single substance or a combination of two or more substances.
The amount of the filler based on 100 weight parts of the solids of the composition is generally not greater than 300 weight parts.
Other particular agents to be added to the composition of the present invention, if desired, are known dehydrating agents including methyl orthoformate, methyl orthoacetate, and tetraethoxysilane; dispersing agents including poly(oxyethylene alkyl ether), poly(oxyethylene alkyl phenyl ether), poly(oxyethylene ester of fatty aid), poly(carbonic acid) polymer surfactant, polycarboxylate, polyphosphate, polyacrylate, polyamide ester salt, and polyethylene glycol; thickening agents including cellulose such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, or hydroxypropylmethyl cellulose, castor oil derivative, and ferrosilicate; inorganic foaming agents including ammonium carbonate, ammonium bicarbonate, ammonium subnitrate, sodium boron hydride, and calcium azide; organic foaming agents including an azo compound such as azobisisobutyronitrile, a hydrazine compound such as diphenylsulfone-3,3xe2x80x2-disulfohydrazine, a semicarbazide compound, a triazole compound, and an N-nitroso compound; and other additives including a surfactant, a silane coupling agent, a titanium coupling agent, and a dye.
Also, a leveling agent may be combined for improving the coating performance of the composition. The leveling agent may commercially be available: as a fluorine leveling agent, BM1000 and BM1100 by BM-Chemie, Efca 772 and Efca 777 by Efca Chemicals, a Florence series by Kyoeisha Chemical, an FC series by SUMITOMO 3M LIMITED, and a Fluonal TF series by Toho Chemical; as a silicone leveling agent, a BYK series by BYK Chemie, a Sshmego series by Sshmegmann, and Efca 30, Efca 31, Efca 34, Efca 35, Efca 36, Efca 39, Efca 83, Efca 86, and Efca 88 by Efca Chemicals; and as an ether or ester leveling agent, Carphynol by Nisshin Chemical and Emargen and Homogenol by Kao Corporation.
The use of the leveling agent will improve the appearance of a finished coating layer and also allow the coating layers to be coated uniformly as a thin film.
The amount of the leveling agent to be used, based on the entirety of the component, is preferably 0.01 to 5 percent by weight and more preferably 0.02 to 3 percent by weight.
Further, the composition of the invention may have a fungus resistance agent corresponding to the purpose of application. The fungus resistance agent may be selected from;
(A) metal ion carrying inorganic fungus resistance agents having carrier such as synthetic zeolite, calcium phosphate, zirconium phosphate, vanadium phosphate, calcium silicate, silicagel, amino acids, metal soaps, ceramics, apatite, activated carbon, montmorinite and depolymerized glass, and metals such as silver, copper, and zinc, and
(B) organic fungus resistance agents such as phenol ethers, sulfons, imidazols, oxybisphenoxyarsine, organic nitrosulfuric compounds, nitrile compounds, benzothiazole compounds, isothiazole compounds, thiadiazole compounds, triazine compounds, pyrrole compounds, and aliphatic imido compounds.
The composition of the present invention or more particularly, the compositions (i) or (ii) for undercoating may be blended with another resin. Characteristic examples of the another resin are acrylic-urethane resin, epoxy resin, polyester, acrylic resin, fluorine resin, acrylic resin emulsion, epoxy resin emulsion, urethane emulsion, and polyester emulsion.
The composition of the present invention which does not include the component (bxe2x80x2), or the composition (ii) maybe blended with the component (bxe2x80x2), water and/or organic solvent. In this case, the amount of the additional component (bxe2x80x2) is the same as above.
The preparation of the coating composition and undercoating composition of the present invention is not limited to a specific mixing method when the two components (c) and (d) are unused. In case that the components (c) and (d) are used, a process may preferably be employed of preparing a mixture of the components (a) to (e) excluding the component (d) and then doping the component (d) into the mixture.
The coating composition of the invention may be produced by the following methods (1) to (4).
(1): A method of adding a specific amount of water to the mixture including organosilane (1) (component (a)), component (b), component (c), and the desired amount of an organic solvent resulting in hydrolyzation and condensation, followed by adding component (d) therein.
(2): A method of adding a specific amount of water to the mixture including organosilane (1) (component (a)) and the desired amount of an organic solvent resulting in hydrolyzation and condensation, followed by adding component (b) and component (c) resulting in condensation, adding component (d) thereafter.
(3): A method of adding a specific amount of water to the mixture including organosilane (1) (component (a)), component (c) and the desired amount of an organic solvent resulting in hydrolyzation and condensation, followed by adding component (b) resulting in partially condensation, adding component (d) thereafter.
(4): A method of adding a specific amount of water to the mixture including, a portion of organosilane (1) (component (a)), component (b), component (c) and the desired amount of an organic solvent, resulting in hydrolyzation and condensation, followed by adding the rest of organosilane (1) resulting in hydrolyzation and condensation, adding component (d) thereafter.
In the present invention, optional components except components (a) to (d) may be added at an appropriate step in preparing the coating composition of the invention.
The concentration of all solids in the coating composition of the present invention is generally 1 to 45 percent by weight, preferably 2 to 40 percent by weight. The solid concentration may be adjusted corresponding to the purpose of application. When the solid concentration in the composition exceeds 45 percent by weight, the storage stability will be declined.
The concentration of all solids in the undercoating composition (i) or (ii) of the present invention is generally not higher than 50 percent by weight, preferably not higher than 40 percent by weight. The solid concentration may be adjusted depending on the type of a substrate, the method of coating, the thickness of a coating layer, and so forth.
Coated Film
The coated film of the present invention consists mainly of a substrate (film)/an undercoating composition (i) or (ii)/a coating composition, or a substrate/a primer/an undercoating composition (i) or (ii)/a coating composition.
The application of any of the compositions of the invention may be conducted by a known manner such as dip coating, flow coating, spraying, screening, electric deposition, vapor deposition, using a brush, a roll coater, a flow coater, a centrifugal coater, an ultrasonic coater, or a (micro) gravure coater.
In forming a layer of the coating composition of the invention on a substrate, the thickness of a coating layer is substantially 0.05 to 20 xcexcm (dried) with single coating application and 0.1 to 40 xcexcm with two times coating application. After dried at an ordinary temperature or heated to 30 to 200xc2x0 C. commonly for 1 to 60 minutes, the coating layer will set on the substrate of a desired type.
In application of the undercoating composition (i) or (ii), the thickness of a undercoating layer is substantially 0.05 to 20 xcexcm (dried), with single undercoating application and 0.1 to 40 xcexcm with two times undercoating application. After dried at an ordinary temperature or heated to 30 to 200xc2x0 C. commonly for 1 to 60 minutes, the undercoating layer will set on the substrate of a desired type.
The total thickness of the undercoating and the overcoating layers may normally be 0.1 to 80 xcexcm and preferably 0.2 to 60 xcexcm after drying.
Corresponding to the use, a primer may also be used in the invention. The primer is not limited to a specific type and may be selected from a variety of materials which enable to enhance the bonding between the substrate and the composition, according to the type of the substrate and the purpose of use. The primer may also be provided in the form of a single substance or a combination of two or more substances. The primer may be an enamel containing a coloring material such as a pigment or may have transparency without such a coloring material.
Characteristic examples of the primer are alkyd resin, aminoalkyd resin, epoxy resin, polyester, acrylic resin, urethane resin, fluorine resin, acrylsilicone resin, acrylic resin emulsion, epoxy resin emulsion, polyurethane emulsion, and polyester emulsion. The primer may have various functional radicals when a higher degree of adhesiveness is required between the film substrate and the coating layer in hostile conditions. The functional radicals include, for example, a hydroxy group, a carboxyl group, an amide group, an amine group, a glycidyl group, an alkoxysilyl group, an ether bond, and an ester bond. The primer may also contain an ultraviolet light absorber, an ultraviolet light stabilizer, and so forth.
For increasing the abrasion resistance and the glossiness of the coating layer of the invention, the coating layer may be protected at the upper surface with a clear layer composed of, for example, a siloxane resin paint which may be a stable dispersion of colloidal silica and siloxane resin such as disclosed in U.S. Pat. Nos. 3,986,997 and 4,027,073.
The substrate film which is able to associate with the composition of the present invention is provided as an organic film selected from polyesters including poly(ethylene terephthalate) (PET), poly(butylene terephthalate) (PBT), and poly(ethylene-2.6-naphthalate) (PEN); polyamides including nylon 6 and nylon 6,6; polyolefins including polyethylene (PE) and polypropylene (PP); polyacryls including polycarbonates (PC) and poly(methacrylate methyl) (PMMA); and ABS resins. The organic film may be a fluorine film such as poly(tetrafluoroethylene) (PTFE) or ethylene-tetrafluoroethylene (ETFE).
The substrate may preliminarily be surface treated for base preparation, improvement in adhesiveness, sealing of porous materials, smoothing, and particular decoration.
Characteristic examples of the surface treatment are blasting, chemical treatment such as alkali treatment, degreasing by a solvent, flaming, oxidation treatment, vapor treatment, corona discharge treatment, UV ozone treatment, ultraviolet radiation, plasma treatment, ion treatment and so forth.
Coated Glass
The coated glass of the present invention consists mainly of a substrate/an undercoating composition (i) or (ii)/a coating composition, or a substrate/a primer/an undercoating composition (i) or (ii)/a coating composition. The application of any of the compositions of the invention may be conducted by the same manner as above coated films.
Substrate Glass
The substrate glass which is able to associate with the composition of the present invention is provided as an inorganic glass such as a clear glass, a green glass, a bronze glass, a tempered glass, a partially tempered glass, a laminated glass, and a glass coated with an ITO conductive film.
The substrate may preliminarily be surface treated for base preparation, improvement in adhesiveness, sealing of porous materials, smoothing, and particular decoration.
The substrate glass of the present invention can be used such as a house window, a front and rear automobile window, a varieties of windows used in a vehicle such as a train, an airplane, a boat, a ship, a top-covered motorcycle, a submarine, a spaceship, a roller coaster, a Ferris wheel; a side and inner mirror of an automobile, a traffic safety mirror set up on the road side, a protection glass used in a device of the generation of electricity such as a protection sheet for a solar cell, a glass used in a monitor, a looking glass, a glass door, and a glass part of a furniture.
With respect to the inorganic glass substrate, characteristic examples of the surface treatment are rubbing, degreasing, metal plating, acid treatment, chroming, flaming, coupling treatment, UV ozone treatment, and so forth.
As set forth above, the coating composition of the present invention enable to provide a coated film and coated glass improved in the resistance to fouling derived from water and oil repellency without declining the adhesiveness, the resistance to weather, heat, alkalis, organic chemicals, moisture, and (hot) water.
The embodiment of the present invention will be described in more detail referring to some examples. It would be understood that the present invention is not limited to the following examples.
The amounts in the examples and their relevant =preparations are denoted in the unit of parts or percent on a weight basis, unless otherwise specified. The measurement and estimation of each characteristic factor was carried out by the following manners.
(1) Mw
A gel permeation chromatography (GPC) method was used under the following conditions.
Test sample: Tetrahydrofuran was used as a solvent. 1 g of a partial condensate of organosilane or 0.1 g of a silyl contained vinyl resin was dissolved in 100 cc of the tetrahydrofran to prepare a test sample. Standard polystyrene: Standard polystyrene made by Pressure Chemical, U.S.A.
Apparatus: A high-temperature, high-speed gel permeation chromatogram (a model, 150-C ALC/GPC) by Waters, U.S.A.
Column: A model, Shodex A-80M (length 50 cm) by SHOW A DENKO K.K., Japan.
Measurement temperature: 40xc2x0 C.
Flow rate: 1 cc/min.
(2) Storage Stability
The coating composition containing no curing accelerator is stored in a bottle of polyethylene at room temperature for 3 months. Then gelation of the coating composition is examined by visual inspection. Viscosity of the composition showing no gelation is measured by BM type viscometer (manufactured by Tokyo Keiki Co. Ltd.). The composition exhibiting a change in a rate of viscosity not more than 20 percent based on that of the initial composition was classified as xe2x80x9cgoodxe2x80x9d.
(3) Adhesiveness
A tape peeling test was conducted three times using a matrix (of 100) specified in JIS K5400 and its average was measured.
(4) Hardness
This measurement was based on a pencil hardness specified by JIS K5400.
(5) Resistance to Alkalis
After a coating test piece was immersed in a saturated calcium hydroxide solution for 60 days, its coating layers were examined visually. The test piece exhibiting no change was classified as xe2x80x9cgoodxe2x80x9d.
(6) Resistance to Organic Chemicals
The coating test piece was applied with 2 cc of isopropyl alcohol, and wiped off after 5 minutes. Then, the test piece was visually examined. The test piece exhibiting no change was classified as xe2x80x9cgoodxe2x80x9d.
(7) Resistance to Moisture
After a test piece was left at a temperature of 50xc2x0 C. and a moisture of 95 RH % for 1,000 hours continuously, its coating layers were visually examined. The test piece exhibiting no change was classified as xe2x80x9cgoodxe2x80x9d.
(8) Resistance to Weather
A 3,000 hours irradiation test with a Sunshine weather meter made by Suga Test was carried out according to JIS K5400 and the coating layers of a test piece were visually examined for the state of appearance (cracking and peeling) The test piece exhibiting no change was classified as xe2x80x9cgoodxe2x80x9d.
(9) Resistance to Water
After a test piece was immersed in tap water at room temperature for 60 days, the coating layer of a test piece were visually examined for the state of appearance (cracking and peeling). The test piece exhibiting no change was classified as xe2x80x9cgoodxe2x80x9d.
(10) Resistance to Hot Water
After a test piece was immersed in hot water at 60xc2x0 C. for 14 days, the coating layers of a test piece were visually examined for the state of appearance (cracking and peeling) The test piece exhibiting no change was classified as xe2x80x9cgoodxe2x80x9d.
(11) Resistance to Fouling
After the coating layer of a test piece were fouled with a mixture paste of carbon black/kerosine oil=1/2 (in weight ratio), left at room temperatures for 24 hours, and rinsed with water using a sponge, the test piece was visually examined. The evaluation was based on the following criteria.
∘: Not fouled.
xcex94: Slightly fouled.
xc3x97: Terribly fouled.
(12) Transparency
The coating composition is coated on quartz glass obtaining a 10 xcexcm thickness (dried) of the coating layer. The transparency of visible radiation of the coating layer is measured. The evaluation was based on the following criteria.
⊚: Transparency higher than 80%.
∘: Transparency between 60 and 80%.
xcex94: Transparency smaller than 60%.
(13) Water and Oil Repellency
A slope angle is measured, at which one drop of water or salad oil (manufactured by THE NISSHIN OIL MILLS, LTD.) on the surface of the above obtained coating layer slips down. The evaluation was based on the following criteria.
∘: slope angle smaller than 60xc2x0.
xcex94: slope angle between 60 and 90xc2x0.
xc3x97: no slip down at a slope angle of 90xc2x0.
(14) Contact Angle
A contact angle of 3 xcexcl of pure water or coal tar (industrial coal tar according to JIS K2439) on the above obtained coating layer is measured by an auto-contact angle meter manufactured by Kyowa Kaimen Kagaku Ltd.
(15) Abrasion Resistance
The coating layer is examined by a taper type abrasion testing machine using abrasion ring of cs-10 at a weight of 0.5 kg and at 500 rotation. The difference between the haze of coating layer before test and that of coating layer after test is examined. The evaluation was based on the following criteria.
∘: difference smaller than 1.
xcex94: difference equal to or smaller than 5.
X: difference greater than 5.
(16) Exfoliation of Stacked Outer Layer
The above coated film is further coated by bisphenol A type epoxy resin to form an outer layer of a thickness of 50 xcexcm. A exfoliation test (of 180xc2x0) is conducted according to JIS K6854-3. The evaluation was based on the following criteria.
∘: the outer layer is released completely.
xcex94: the outer layer is released partially.
xc3x97: the outer layer is not released.
Preparation 1 (of the Component (b))
A stainless autoclave equipped with an electromagnetic stirrer was subjected to substitution with a nitrogen gas and filled with 150 parts of methyl isobutyl ketone, 30 parts of ethyl vinyl ether, and 2 parts of lauroyl peroxide (a radical polymerization initiator). The reaction mixture was cooled down to xe2x88x9250xc2x0 C., and then deoxygenated using nitrogen gas. Then, 65 parts of hexafluoropropylene and 5 parts of vinyltrimethoxysilane was added to the reaction mixture and it was heated up. When the temperature in the autoclave was increased up to 60xc2x0 C., the interior pressure was 5 kgf/cm2.
The mixture was stirred for 20 hours at 60xc2x0 C. to complete the polymerization reaction. When the pressure in the autoclave dropped down to 1.5 kgf/cm2, the mixture was cooled down with water to quench the reaction. The total solid content of the polymer solution was 40% (referred to as (B-1)).
Preparations 2 to 5 (of the Component b).
By the same manner as of Provision 1 except for the monomers used as shown in Table 1, polymer solutions (B-2 to B-5) having a solid concentration of 40% were prepared.
Preparation 6 (of the Component (bxe2x80x2)(Silyl Group Having Polymer))
In a reactor equipped with a circulating cooler and a stirrer, 70 parts of methyl methacrylate, 40 parts of n-butyl acrylate, 20 parts of xcex3-methacryloxypropyltrimethoxysilane, 7 parts of acrylic acid, 13 parts of 2-hydroxyethyl methacrylate, 150 parts of i-propyl alcohol, 50 parts of methyl ethyl ketone, and 25 parts of methanol were mixed up. The mixture was then heated to 80xc2x0 C. while being stirred and 4 parts of azobisisovaleronitrile dissolved into 10 parts of xylene was added gradually for 30 minutes. After the reaction mixture was kept at 80xc2x0 C. for 5 hours, a polymer solution (referred to as (bxe2x80x2-1) hereinafter) having a solid concentration of 40% was obtained.